Hitachi Universal Storage Platform VM User Manual
Page 58
3-14
Functional and Operational Characteristics
Hitachi Universal Storage Platform V/VM User and Reference Guide
Mode
Category
Function
Default
MCU/RCU
454
Virtual Partition
Manager
When making a destage schedule for CLPRs, using the
average workload of all the CLPRs or the highest workload of
those of the CLPRs can be optional.
Mode 454 = ON: The average workload of all the CLPRs is
used to make the destage schedule.
Mode 454 = OFF: The highest workload of those of the CLPRs
is used to make the destage schedule.
Note: The priority of the destage processing for a specific
CLPR in the overloaded status decreases and the overloaded
status is not released so that TOV (MIH) may occur.
OFF –
457
Universal Volume
Manager
(1) High Speed LDEV Format for External Volumes
Mode 457 = ON: The high speed LDEV format for external
volumes is available by setting system option mode 457 to
ON. When System Option Mode 457 is ON, when selecting the
external volume group and performing the LDEV format, any
Write processing on the external LUs will be skipped.
However, if the emulation type of the external LDEV is a
mainframe system, the Write processing for mainframe
control information only will be performed after the write skip.
(2) Support for Mainframe Control Block Write GUI
Mode 457 = ON: The high speed LDEV format for external
volumes is supported. Control Block Write of the external
LDEVs in Mainframe emulation is supported by Storage
Navigator (GUI).
Note:
If the LDEV is not written with data “0” before performing
the function, the LDEV format may fail.
After the format processing, make sure to set system
option mode 457 to OFF.
OFF MCU/RCU
459
ShadowImage for
z/OS
ShadowImage
When the secondary volume of an SI/SIz pair is an external
volume, the transaction to change the status from SP-PEND to
SPLIT is as follows:
(1) Mode 459 = ON when creating an SI/SIz pair: The copy
data is created in cache memory. When the write processing
on the external storage completes and the data is fixed, the
pair status will change to SPLIT.
(2) Mode 459 = OFF when creating an SI/SIz pair Once the
copy data has been created in cache memory, the pair status
will change to SPLIT. The external storage data is not fixed
(current spec).
OFF –